Third Trimester

Pregnancy Week 33

Your baby is about the size of a pineapple 🍍bones hardening, skull stays soft.

Week 32Week 33 / 40Week 34
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Size comparison

Pineapple

Length

43.7 cm

Weight

1.9 kg

Milestone

Bones hardening, skull stays soft

About 7 weeks to go until your due date (week 40).

Baby's development at week 33

Most bones are hardening but the skull remains soft and flexible — essential for passage through the birth canal. The immune system is receiving a final wave of antibodies from you.

Eat smaller portions more frequently to manage heartburn as the baby crowds your stomach.

Common symptoms at week 33

Heartburn severePelvic pressureBack acheOedema

Eat more of

  • Calcium & Vitamin K (broccoli, kale)
  • DHA-rich fish (sardines, salmon — cooked)
  • Iron-rich foods to prevent anaemia
  • Fibre-rich foods to combat constipation
  • Small frequent meals to ease heartburn
  • Dates (studies suggest easier labour)

Foods to avoid

  • Alcohol
  • Gas-producing foods (beans, cabbage) if uncomfortable
  • Very spicy food if causing heartburn
  • Raw/undercooked meat
  • High-sodium processed food
  • Large meals that worsen reflux

Medically reviewed by First OPD Medical Team. Last reviewed on .

Based on average milestones from World Health Organization (WHO), ACOG, NHS UK. Educational only — not a substitute for personalised medical advice.

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